# OB Datum: Pregnancy Dating — EDD, IVF & Gestational Age

> EDD, IVF & Gestational Age (iPhone/iPad app by VLR Software.)

- Source: https://appshunter.io/ios/app/ob-datum-pregnancy-dating/id6799726065 (this page in markdown: same URL + `.md`)
- Developer: [VLR Software](https://appshunter.io/developer/375047405)
- Category: Medical, Health & Fitness
- Price: $1.99 with in-app purchases
- Age rating: 17+
- Requires: iOS 26.0 · 8 MB
- Languages: American English, European Spanish
- Released: 2026-09-02
- Data updated: 2026-10-15

## What is OB Datum?

Calculate and compare pregnancy dates with a clear explanation of every result.

OB Datum is a clinician-first pregnancy-dating workspace for iPhone and iPad. It performs deterministic calendar arithmetic and shows the source, formula, equivalent dates, and calculation-engine version for review.

CALCULATE FROM

• First day of the last menstrual period, with optional regular-cycle adjustment
• Documented conception or ovulation date
• An established estimated due date
• Gestational age documented on a known date
• IVF embryo-transfer date and documented embryo age

EVERY FEATURE INCLUDED

Every dating method, read-only Health import, full dating reconciliation, unlimited anonymous saved cases, formatted sharing, Calendar export, and custom timeline milestones are included in the downloaded app. There is no subscription, advertising, or separate feature purchase.

In Reconcile, keep an established EDD locked while comparing the dates implied by LMP, ultrasound gestational age, and IVF/ART. OB Datum reports signed calendar-day differences and never changes, averages, or recommends changing the established EDD.

EXPLORE THE TIMELINE

Calculate gestational age on a selected date, find the date corresponding to a gestational age, review descriptive milestones, and explore an interactive pregnancy wheel with accessible day and exact-date controls.

PRIVATE BY DESIGN

• No advertising or tracking
• No patient names, record numbers, contact details, or notes
• Anonymous saved calculations stay protected on your device
• Optional read-only import of the latest menstrual-cycle start from Health
• Calendar export includes only the EDD and no patient identifiers
• The widget opens OB Datum without displaying pregnancy or case data

OB Datum also provides a privacy-safe due-date action for Shortcuts and shareable calculation summaries.

OB Datum supports date arithmetic and clinical review. It does not diagnose, prescribe, select a delivery date, or replace professional judgment. Independently verify every input, result, and source before clinical use.

## Pricing and in-app purchases

Base price: $1.99.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| OB Datum Lifetime Pro | $1.99 | one-time |


## Is OB Datum safe?

Not enough ratings yet to assess OB Datum.

## Is OB Datum legit?

OB Datum: Pregnancy Dating appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for OB Datum is 75 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 2 releases)

### 1.1 — 2026-09-15

Every OB Datum feature is now included in the downloaded app. Use known gestational age, IVF/ART dating, Health import, Reconcile, unlimited anonymous cases, sharing, Calendar export, and custom milestones without a separate in-app purchase. Clinical sources now appear as non-interactive bibliography. Calculations remain private, offline, and independently reviewable.

### 1.0 — 2026-09-03

No release notes.

## Apps similar to OB Datum

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Perfect OB Wheel](https://appshunter.io/ios/app/perfect-ob-wheel/id293656711) | 4.9 (3,578) | $1.99 | Medical |
| [BioDigital - 3D Human Anatomy](https://appshunter.io/ios/app/biodigital-3d-human-anatomy/id771825569) | 4.6 (3,971) | Free | Medical |

## More apps by VLR Software

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- [ICD 10 On the Go 2027](https://appshunter.io/ios/app/icd-10-on-the-go-2027/id377273816)
- [ICD9 On the Go](https://appshunter.io/ios/app/icd9-on-the-go/id395106691)
- [ICD Medical Codes 2027](https://appshunter.io/ios/app/icd-medical-codes-2027/id723770850)
- [ICD 10 2027](https://appshunter.io/ios/app/icd-10-2027/id878887635)

All apps by VLR Software: https://appshunter.io/developer/375047405

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-15.*